232 TANK REPLACEMENT: deck flange trimming & cross bracing

[NIGHTIDES]

Re-coring deck over main gas tank and decided to change out the 27 year old tank despite the absence of a leak.

Pulled the deck and notice right away that the cross-bracing 2x4's had about 1/2 - 3/4" clearance from the top of the tank. Thought that to be unusual since a tank I did on a different Grady years ago had those wood members w/ neoprene tight to the tank.

Has anyone else seen this when they did their tanks?? Never thought the tank may have settled but this has me thinking.

Also it seems that I will need to trim the deck flange 1/8 - 1/4" to get out the old and put in the new. What would be the best and cleanest method to get this done? Really want to keep this process as clean as I can.

Thank you for your help.

 

[Ky Grady]

A belt sander came in handy when I removed my tanks from my 228. Removed about the same amount of material too. Keeping it clean will be an understatement. You will generate some dust for sure.

 

[SkunkBoat]

hijacking this thread for a question about grady design.
My 265 Express tanks were replaced 5 months before I bought the boat so I won't be changing them in my lifetime but I am repairing the deck lid
The picture shows 2 short pvc drain tubes that pass bilge water into and out of the the tank space..yes?
and there is a "false floor" that the tank sits on and the bilge water flows under the tank?
So I can wash the tanks and the space and it will drain out no problem...yes?

Asking because in my previous boats with foamed in tanks, the tank compartment was sealed and bilge water passed thru a long pvc pipe under the tank. No water was ever supposed to enter the space.

 

[SmokyMtnGrady]

hijacking this thread for a question about grady design.
My 265 Express tanks were replaced 5 months before I bought the boat so I won't be changing them in my lifetime but I am repairing the deck lid
The picture shows 2 short pvc drain tubes that pass bilge water into and out of the the tank space..yes?
and there is a "false floor" that the tank sits on and the bilge water flows under the tank?
So I can wash the tanks and the space and it will drain out no problem...yes?

Asking because in my previous boats with foamed in tanks, the tank compartment was sealed and bilge water passed thru a long pvc pipe under the tank. No water was ever supposed to enter the space.

It should . They put the PVC in there to get water from the bow to the stern for drainage. now, with that said , sometimes those tubes can get clogged, especially with chunks of fiberglass from the build. I washed my tank last year and rinsed the compartment with fresh waters and soap. it drained fine . You should be good to go cleaning it.

 

[DennisG01]

Nighttides - another option for the tank removal/install process. Rather than cutting any part of the boat, cut the tank. You'll need to get rid of all the gas... siphon it all, then siphon again, then let it opened up for a week. Then fill the tank with water till over flows for about 10 minutes. Now you can cut the tank without worrying about gas fumes and sparks. For the new tank... change the dimensions by just enough to drop it in there.

If you do decide to cut... a reciprocating tool, while slower, will not throw dust into the air - it will pretty much just drop straight down. Holding a vacuum near it will catch most of it.

It's definitely better to have an air gap between the tank and anything else whenever possible. Unless that neoprene is fully, 100% sealed to the tank (and STAYS that way over time), moisture can get in between the tank and the neoprene and cause pitting/holes. Aluminum self protects itself from corrosion, but only if it has air on it.

 

[leeccoll]

Used a Sawzall to trim the lip slightly. Was both easy to do and a giant mess. Even dust got all over the inside of my cuddy cabin.

Nothing a shop vac and a few cold beers can't handle.

 

[NIGHTIDES]

Thanks to all for this helpful information.

Comments:

- cutting the tank instead may have been a viable option before I ordered the replacement per OEM drawings. Maybe a quick call Monday to the fabricator will reveal this option as being available.
- neoprene stuck directly to the tank makes a world of sense instead of 5200 the strips to the belly of the boat. What adhesive? Same 4200-5200-Life Seal I would think.
- still do not want to dust everything up and have to deal with the resulting toxic mess/environment. Shop vac will definitely be invited to the party and a mask but still looking for ideas for the cleanest method possible.

Also before feeding the hose from the deck fill connecting to old hose, old hose is in the way of the tank removal. I assume just back the hose out of the way just behind the bulkhead temporarily until the tank is out then reintroduce it and pull the new hose through in tow.

 

[leeccoll]

If you get someone to hold the shop vac while you cut or grind out the lip, it will help a lot. I used 5200 on my replacement, but to each their own.

The hoses are super stiff, especially the fill hose. Just be careful you don't slide it in the bulkead and it goes on a new journey inside there.

You might want to entertain changing the hoses out as well, you won't have a better opportunity once you "yank the tank".

 

[Blaugrana]

hijacking this thread for a question about grady design.
My 265 Express tanks were replaced 5 months before I bought the boat so I won't be changing them in my lifetime but I am repairing the deck lid
The picture shows 2 short pvc drain tubes that pass bilge water into and out of the the tank space..yes?
and there is a "false floor" that the tank sits on and the bilge water flows under the tank?
So I can wash the tanks and the space and it will drain out no problem...yes?

Asking because in my previous boats with foamed in tanks, the tank compartment was sealed and bilge water passed thru a long pvc pipe under the tank. No water was ever supposed to enter the space.

I took mine off this past winter, cleaned off the tank and sprayed a ton of water in there to wash out the years of salt that might have built up over the years.

It all drained into the bilge....Depending on how tilted your boat is, you may need to help the water drain into the bilge....I had to use a wet/ dry vac to suck up the water from that PVC pipe running into the bilge

 

[NIGHTIDES]

If you do decide to cut... a reciprocating tool, while slower, will not throw dust into the air - it will pretty much just drop straight down. Holding a vacuum near it will catch most of it.

Worked like a charm. Thanks.

 

[DogBone]

I see you have already cut yours out, so you will not need this technique for removal. However doing this for installing is necessary also. When installing, place the forward end into the cavity and keep a strap under the forward and aft ends. Then, raise the forward end as high in the cavity as possible with it hitting the underside of the deck. Then as you lower the aft end into the cavity, it should just clear at this angle. It will not clear the aft bulkhead if the forward end of the tank is all the way on the bottom. I just went through this on my 232 this Summer.

 

[DennisG01]

Worked like a charm. Thanks.

You're welcome!

 

[blindmullet]

Asking because in my previous boats with foamed in tanks, the tank compartment was sealed and bilge water passed thru a long pvc pipe under the tank. No water was ever supposed to enter the space.

Those foamed in tanks would have done so much better with some glass around the perimeter and a drain on top draining to the bilge. My son and I just did this to our mako.